Cooling system for a cryochamber

ABSTRACT

A cooling system for a cryochamber comprises compressors, heat exchangers and flow restrictions. Compressors are used to pressurize the working fluid, heat exchangers are used to release the heat to the ambient, absorb heat from the interior of the cryochamber to decrease the temperature inside the cryochamber, to cool the working fluid below the ambient temperature using source of cold or to recuperate heat of the cold working fluid stream. Flow restrictions are used to decrease the pressure of the working fluid which results in its temperature decrease. Cryochambers are used for whole-body cryotherapy and require cooling systems that are able to lower the air temperature inside the cryochamber to −90° F.

FIELD OF THE INVENTION

The present invention relates to a cooling system for an interior of a cryochamber.

BACKGROUND OF THE INVENTION

Cryochambers are used in whole-body cryotherapy, where user stays inside the insulated space for a set duration of time in very low temperature (−90° F. and below). In order to provide the best experience to the user, cooling system of the cryochamber has to have cooling capacity high enough to cool down air inside cryochamber in the shortest time possible, and have high efficiency to maximize economical value, as well as be as easy to maintain and service.

SUMMARY OF THE INVENTION

In order to solve challenges mentioned above, a cooling system for a cryochamber is proposed, comprising at least one compressor, at least one heat exchanger releasing heat to the ambient, at least one heat exchanger inside the cryochamber, at least one flow restriction and at least one recuperative heat exchanger.

Working fluid flows through the compressor where it gets pressurized, next it releases heat to the ambient in the heat exchanger, from which it flows through flow restriction where it decreases its pressure and temperature. Cooled working fluid flowing out of the restriction then absorbs heat from the interior of the cryochamber in the heat exchanger and returns to the compressor. An extra step may be included where working fluid is cooled inside an additional heat exchanger instead of releasing heat to the ambient, or working fluid releases heat both to the ambient and to the source of cold in order to improve efficiency of the cycle. In addition to mentioned cycle efficiency increase methods, a recuperative heat exchanger may be also used to improve the efficiency even more by transferring heat from working fluid stream after it released heat to the ambient to the cold working fluid stream flowing out of the heat exchanger inside the cryochamber.

A wide variety of working fluids and their mixtures may be used, as long as their boiling point is below −90° F.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure, operating principle and effects of the present invention will be described in detail by way of various embodiments which are illustrated in the accompanying drawings.

FIG. 1 is a schematic of a first cooling system.

FIG. 2 is a schematic of a second cooling system.

FIG. 3 is a schematic of a third cooling system.

FIG. 4 is a schematic of a fourth cooling system.

FIG. 5 is a graph of the temperature inside a cryochamber and the temperature at a inlet to a heat exchanger inside the cryochamber as a function of time, during the cooling process of the cryochamber.

FIG. 6 is a graph of the temperature inside the cryochamber and the temperature at the inlet to the heat exchanger inside the cryochamber as a function of time, under typical workload.

FIG. 7 is a flowchart illustrating an example method for cooling a cryochamber.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following embodiments of the present invention are herein described in detail with reference to the accompanying drawings. These drawings show specific examples of the embodiments of the present invention. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It is to be acknowledged that these embodiments are exemplary implementations and are not to be construed as limiting the scope of the present invention in any way. Further modifications to the disclosed embodiments, as well as other embodiments, are also included within the scope of the appended claims. These embodiments are provided so that this disclosure is thorough and complete, and fully conveys the inventive concept to those skilled in the art. Regarding the drawings, the relative proportions and ratios of elements in the drawings may be exaggerated or diminished in size for the sake of clarity and convenience. Such arbitrary proportions are only illustrative and not limiting in any way. The same reference numbers are used in the drawings and description to refer to the same or like parts.

It will be acknowledged that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer, it can be directly on connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present.

In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be acknowledged to imply the inclusion of stated elements but not the exclusion of any other elements.

Embodiments of the disclosure provide a cooling system for a cryochamber.

FIG. 1 illustrates an example cooling system 100 for a cryochamber that cools the interior of the cryochamber 170 to cryogenic temperatures. For example, the cooling system 100 can cool the interior between −148° F. to −256° F. The cooling system 100 reaches these temperatures using one or two compressors. In contrast, cryogenic cascade refrigerator cannot reach the cryogenic temperatures using one or two compressors. The cooling system 100 reaches cryogenic temperatures with one or two compressors because the working fluid includes multiple refrigerants with different boiling points. For example, the working fluid can include five different refrigerants with different boiling points. In these instances, the cooling system 100 is a closed system including the five refrigerants with different boiling points. The five different refrigerants can provide cooling power under different pressures such as a high-pressure stream versus a low-pressure stream. The working fluid can include more five or less five refrigerants with each having a different boiling point without departing from the scope of the disclosure.

In the five-refrigerant example, the working fluid can include R-134a, R-23, R-116, R-218 and R-14. In these instances, the molar ratios for individual refrigerants can be within following ranges: R-134a (10-20%), R-23 (15-25%), R-116 (20-40%), R-218 (25-40%), R-14 (30-50%). The sum of the molar ratios of the five refrigerants will add to 100%. As previously mentioned, the cooling system 100 can include a working fluid with more or less than five refrigerants without departing from the scope of the disclosure. In some instances, the working fluid may include one or more of the following refrigerants: R-134a, R-218, R-116, R-23, R-14, R-32, R-728, R-50, R-170, R-290, R-22, R-125, R-600a, R-600, R-1270, R-1234yf, R-1234ze, R-740, R-744, R-1150, and/or others.

As illustrated, the cooling system 100 includes a compressor 110, a heat exchanger 120 releasing heat to the ambient, a flow restriction 130, an inner heat exchanger inside the cryochamber 170, and a recuperative heat exchanger 150. The compressor 110 pressurizes the working fluid, and then at least a portion of the working fluid releases heat through the heat exchanger 120. In some case, the pressure after the compressor 110 is in the range of 140 psi to 500 psi and has a temperature up to 302° F. In high-pressure systems, the pressure after the compressor can reach up to 900 psi. The compressor 110 can be single stage or multi stage, multiple compressors can also work together and be connected either in parallel or serial manner without departing from the scope of the disclosure.

As previously mentioned, the heat exchanger 120 cools the working fluid to, for example around 70° F., which can be close to ambient temperature. After the heat exchanger 120, the working fluid pass through the recuperative heat exchanger 150, which further cools the working fluid. The pressure behind flow restrictor 130 can be in the range of 7 to 100 psi. The cooled working fluid then passes through the flow restrictor 130 that has a positive Joule-Thomson coefficient. Once working fluid exits the flow restrictor 130, the pressure decreases that results in a temperature decrease. The temperature can cool to a range of −60° F. to −230° F. Flow restrictor 130 can be any element or plurality of elements that provide sufficient hydraulic resistance (including, but not limited to elements such as porous plug, valve or capillary tube, throttling value, other restrictors, or a combination thereof).

After the flow constrictor 130, the cooled working fluid pass through the inner heat exchanger 140 in the cryochamber 170 and absorbs heat from the interior of the cryochamber 170, which results in a temperature decrease inside the cryochamber 170. The temperature of the interior of the cryochamber 170 can be −90° F. or less. The working fluid then passes through the recuperative heat exchanger 150 and cools the working fluid passing from the ambient heat exchanger 120 to the flow restrictor 130. Once cooled, the working fluid enters the compressor 110, and the cooling system can be a closed cycle. In some instances, the system can work in a continuous manner. The heat exchangers 120, 140 and/or 150 can include multiple heat exchangers connected in parallel, serial manner, or combination thereof without departing from the scope of the disclosure.

FIG. 2 illustrates a second cooling system 200 that include a external cooling source 202. The cooling system 200 includes a compressor 210, a heat exchanger 220, a heat exchanger 260 in contact with the cooling source 202, a flow restrictor 230, an inner heat exchanger 240 inside the cryochamber 270, and a recuperative heat exchanger 250. The heat exchanger 260 cools the working fluid below ambient using the external cooling source 202. The external cooling source 202 can, in some implementations, cold tap water, a chilled fluid (e.g., water, brine, others), a standard refrigeration Linde cycle, other cold sources, or a combination thereof.

In this embodiment, the compressor 210 pressurizes the working fluid, and then it releases heat to the ambient in the heat exchanger 220. The cooled working fluid flows through heat exchanger 260 in contact with the cooling source 202, which cools working fluid further. In the heat exchanger 260, the working fluid releases heat to the cooling source 202. The working fluid can be cooled below ambient temperature before it flows through recuperative heat exchanger 250. The cooling source 202 can result in lower temperature of the working fluid stream at the outlet of the recuperative heat exchanger 250 and, as a result, higher cooling capacity can be achieved when the working fluid passes through flow restrictor 230. As previously mentioned, sources of cold can include, but are not limited to, chilled water, brine add/or another cooling system.

The working fluid then passes through recuperative heat exchanger 250. The recuperative heat exchanger 250 additionally cools down the working fluid passing from the heat exchanger 260 to the flow constrictor 230. The recuperative heat exchanger 250 uses the working fluid returning from the inner heat exchanger 240 inside the cryochamber 270. After exiting the recuperative heat exchanger 250, the flow restrictor 230 decrease the pressure and temperature of the working fluid before entering the inner heat exchanger 240. The working fluid then absorbs heat from the interior of the cryochamber 270 as it passes through the inner heat exchanger 240. Next, the working fluid exists the inner heat exchanger 240 and passes through recuperative heat exchanger 250 and then is pressurized in the compressor 210, and the cycle can be closed.

FIG. 3 depicts a third cooling system 300 including a cooling source 302. As illustrated, the cooling system 300 includes compressors 310 and 311, heat exchanger 320 releasing heat to, for example, the ambient, flow restrictors 330 and 331, an inner heat exchanger inside the cryochamber 370, recuperative heat exchanger 350 and heat exchanger 360 in contact with the cooling source 302.

In this embodiment, the working fluid is pressurized in the compressor 310, and then it is cooled below the ambient temperature by the cooling source 302 in contact with the heat exchanger 360. The recuperative heat exchanger 350 further cools the working fluid using the cooler working fluid returning from the inner heat exchanger 370 inside the cryochamber 370. Working fluid then flows through the flow restrictor 330, which decreases the temperature and pressure of the working fluid. The working fluid flows through the inner heat exchanger 340, which cools the interior of the cryochamber 370. The cold working fluid flows through recuperative heat exchanger 350, and then the compressor 310 pressurizes the working fluid, which closes the cycle.

In some implementations, the cooling source 302 can be a standard refrigeration cycle using standard refrigerants such as R-404a, R-407C, and/or others. In this instance, the cooling source 302 includes another cooling system 304. The cooling system 304 includes a compressor 311, a heat exchanger 320 releasing heat to, for example the ambient and a flow restrictor 331. In operation, the compressor 311 compresses the work fluid and the compressed working flow passes the heat exchanger 320, which cools the working fluid. The working fluid exits the heat exchanger 320 and pass through the flow restrictor 331, which decreases pressure and the temperature of the working fluid. The working fluid after exiting the flow restrictor 331 passes through the heat exchanger 360, which cools the working fluid in the cooling system 302. The cooling system 304 absorbs heat from the cooling system 302 for the cryochamber 370, which can increase the efficiency of the cooling system 302.

FIG. 4 depicts a fourth cooling system 400 including a cooling source 402. The cold system 400 includes compressors 410 and 411, a heat exchanger 420, flow restrictors 430 and 431, an inner heat exchanger 440 inside the cryochamber 470, recuperative heat exchangers 450 and 451, and the heat exchanger 460 cooling working fluid below the ambient temperature.

In this embodiment, the compressor 410 pressurizes the working fluid, and then the pressurized working fluid is cooled below the ambient temperature using the cooling source 402 in contact with the heat exchanger 460. After exiting the heat exchanger 460, the recuperative heat exchanger 450 further cools the working fluid using the cooler working fluid returning from the inner heat exchanger 470 inside the cryochamber 470. Working fluid then flows through the flow restrictor 430, which decreases the temperature and pressure of the working fluid. The working fluid flows through the inner heat exchanger 40, which cools the interior of the cryochamber 470. The cold working fluid flows through recuperative heat exchanger 450, and then the compressor 410 pressurizes the working fluid, which closes the cycle.

In this instance, the cooling source 402 includes another cooling system 404. The cooling system 404 includes a compressor 411, a heat exchanger 420 releasing heat to, for example the ambient, a recuperative heat exchanger 451, a flow restrictor 431, and the heat exchanger 460. In operation, the compressor 411 compresses the work fluid and the compressed working passes through the heat exchanger 420, which cools the working fluid. The working fluid exits the heat exchanger 420 and pass the recuperative heat exchanger 451, which further cools the working fluid. The working fluid exits the recuperative heat exchanger 451 and passes the flow restrictor 431, which decreases pressure and the temperature of the working fluid. After exiting the flow restrictor 431, the working fluid passes through the heat exchanger 460, which cools the working fluid in the cooling system 402. The cooling system 404 absorbs heat from the cooling system 402 for the cryochamber 470, which can increase the efficiency of the cooling system 402.

FIG. 5 is a graph of air temperature and working fluid temperature as a function of time during the cooling process. The air temperature is inside a cryochamber and temperature of the working fluid is at the inlet to the heat exchanger inside cryochamber during process of cooling from the ambient temperature of 50° F. to the operating temperature of −166° F. In some instances, the cooling process can take less than 90 minutes, after that time cryochamber is ready for use.

FIG. 6 is a graph of air temperature and working fluid temperature as a function of time during a typical workload. The air temperature is inside the cryochamber, and the temperature of the working fluid is at the inlet to the heat exchanger inside cryochamber. The increase in temperature from the time of 152 min to 155 min is caused by the cryochamber door opening and closing when users are entering and walking out of the cryochamber, and the heat produced by four users which are staying inside the cryochamber for the duration of the session. Temperature increase observed from the time of 157 min to 160 min is from the cryochamber door opening and closing when users are entering and exiting the cryochamber, and the heat produced by two users that are staying inside the cryochamber for the duration of the session. Another temperature increase, from the time of 164 min to 167 min is caused by the cryochamber door opening, closing, and next two users that are staying inside the cryochamber for the duration of the session. The last temperature increase from the time of 186 min to 190 min is from the cryochamber door opening, closing, and heat produced by a single user that stays inside the cryochamber for the duration of the session.

FIG. 7 is a flowchart illustrating an example method for cooling a cryochamber using at least five refrigerants. 

What is claimed is:
 1. A cooling system, comprising: a working fluid including at least two different refrigerants with different boiling points; a compressor having an inlet configured to receive the working fluid and fluidically connected to an outlet of an inner heat exchanger and an outlet fluidically connected to an inlet of a heat exchanger; the heat exchanger including an outlet fluidically connected to a first inlet of a recuperative heat exchanger; the recuperative heat exchanger including a first outlet fluidically connected to an inlet of a flow constrictor and a second inlet fluidically connected to an outlet of the inner heat exchanger and a second outlet fluidically connected to the inlet of the compressor; the flow restrictor including an outlet fluidically connected to an inlet of the inner heat exchanger; and the interior heat exchanger including a surface configured to receive with surrounding air.
 2. The cooling system for a cryochamber according to claim 1, the heat exchanger in contact with an external source of cold.
 3. The cooling system of claim 2, wherein the external source of cold comprises a cold fluid.
 4. The cooling system of claim 2, wherein the working fluid comprising a first working fluid, the compressor comprises a first compressor, the heat exchanger comprises a first heat exchanger, the inlet of the first heat exchanger comprising a first inlet of the first heat exchanger, the outlet of the first heat exchanger comprising a first outlet of the first heat exchanger, the flow restrictor comprising a first flow restrictor, the external source of cold comprising a second cooling system comprising: a second working fluid including one or more refrigerants with different boiling points; a second compressor having an inlet configured to receive the second working fluid and fluidically connected to a second outlet of the first heat exchanger and an outlet fluidically connected to an inlet of a second heat exchanger; the second heat exchanger including an outlet fluidically connected to an inlet of a second flow restrictor; and the second flow restrictor including an outlet fluidically connected to a second inlet of the first heat exchanger.
 5. The cooling system of claim 2, wherein the working fluid comprising a first working fluid, the compressor comprises a first compressor, the heat exchanger comprises a first heat exchanger, the flow restrictor comprising a first flow restrictor, the inlet of the first heat exchanger comprising a first inlet of the first heat exchanger, the outlet of the first heat exchanger comprising a first outlet of the first heat exchanger, the external source of cold comprising a second cooling system comprising: a second working fluid including one or more refrigerants with different boiling points; a second compressor having an inlet configured to receive the second working fluid and fluidically connected to a second recuperative heat exchanger and an outlet fluidically connected to an inlet of a second heat exchanger; the second heat exchanger including an outlet fluidically connected to a first inlet of a second recuperative heat exchanger; the second recuperative heat exchanger including a first outlet fluidically connected to an inlet of a second flow constrictor and a second inlet fluidically connected to a second outlet of the first heat exchanger and a second outlet fluidically connected to the inlet of the second compressor; and the second flow restrictor including an outlet fluidically connected to a second inlet of the first heat exchanger.
 6. The cooling system of claim 1, wherein fluidically connected comprises connected using conduits.
 7. The cooling system of claim 1, wherein the working fluid includes at least five different refrigerants with each having a different boiling point.
 8. A cryochamber, comprising: a cooling system, comprising: a working fluid including at least two different refrigerants with different boiling points; a compressor having an inlet configured to receive the working fluid and fluidically connected to an outlet of an inner heat exchanger and an outlet fluidically connected to an inlet of a heat exchanger; the heat exchanger including an outlet fluidically connected to a first inlet of a recuperative heat exchanger; the recuperative heat exchanger including a first outlet fluidically connected to an inlet of a flow constrictor and a second inlet fluidically connected to an outlet of the inner heat exchanger and a second outlet fluidically connected to the inlet of the compressor; the flow restrictor including an outlet fluidically connected to an inlet of the inner heat exchanger; and the interior heat exchanger including a surface configured to receive with surrounding air.
 9. The cryochamber of claim 8, the heat exchanger in contact with an external source of cold.
 10. The cryochamber of claim 9, wherein the external source of cold comprises a cold fluid.
 11. The cryochamber of claim 9, wherein the working fluid comprising a first working fluid, the compressor comprises a first compressor, the heat exchanger comprises a first heat exchanger, the inlet of the first heat exchanger comprising a first inlet of the first heat exchanger, the outlet of the first heat exchanger comprising a first outlet of the first heat exchanger, the flow restrictor comprising a first flow restrictor, the external source of cold comprising a second cooling system comprising: a second working fluid including one or more refrigerants with different boiling points; a second compressor having an inlet configured to receive the second working fluid and fluidically connected to a second outlet of the first heat exchanger and an outlet fluidically connected to an inlet of a second heat exchanger; the second heat exchanger including an outlet fluidically connected to an inlet of a second flow restrictor; and the second flow restrictor including an outlet fluidically connected to a second inlet of the first heat exchanger.
 12. The cryochamber of claim 9, wherein the working fluid comprising a first working fluid, the compressor comprises a first compressor, the heat exchanger comprises a first heat exchanger, the flow restrictor comprising a first flow restrictor, the inlet of the first heat exchanger comprising a first inlet of the first heat exchanger, the outlet of the first heat exchanger comprising a first outlet of the first heat exchanger, the external source of cold comprising a second cooling system comprising: a second working fluid including one or more refrigerants with different boiling points; a second compressor having an inlet configured to receive the second working fluid and fluidically connected to a second recuperative heat exchanger and an outlet fluidically connected to an inlet of a second heat exchanger; the second heat exchanger including an outlet fluidically connected to a first inlet of a second recuperative heat exchanger; the second recuperative heat exchanger including a first outlet fluidically connected to an inlet of a second flow constrictor and a second inlet fluidically connected to a second outlet of the first heat exchanger and a second outlet fluidically connected to the inlet of the second compressor; and the second flow restrictor including an outlet fluidically connected to a second inlet of the first heat exchanger.
 13. The cryochamber of claim 8, wherein fluidically connected comprises connected using conduits.
 14. The cryochamber of claim 8, wherein the working fluid includes at least five different refrigerants with each having a different boiling point.
 15. A method, comprising: receiving a working fluid, wherein the working fluid includes at least two different refrigerants with different boiling points; compressing the received working fluid; releasing heat from the received working fluid to generate a first cooled working fluid; releasing additional heat from the first cooled working fluid to a cooled portion of the working fluid to generated a second cooled working fluid; constricting flow of the second cooled working fluid to generated a constricted working fluid; decreasing pressure of the constricted working fluid to generated a third cooled working fluid; and releasing heat from a cryochamber using the third cooled working fluid to generated the cooled portion of the working fluid.
 16. The method of claim 15, the first cooled working fluid is generated using an external source of cold.
 17. The method of claim 16, wherein the external source of cold comprises a cold fluid.
 18. The method of claim 16, wherein the external source of cold comprises a second cooling system, the working fluid comprising a first working fluid, the method further comprising: compressing a second working fluid including one or more refrigerants with different boiling points; releasing heat from the compressed second working fluid to generated a fourth cooled working fluid; constricting flow of the fourth cooled working fluid to generated a constricted fourth cooled working fluid; and releasing pressure of the constricted fourth cooled working fluid to generated a fifth cooled working fluid, wherein the first cooled working fluid is generated using the fifth cooled working fluid.
 19. The method of claim 16, wherein the external source of cold comprises a second cooling system, the working fluid comprising a first working fluid, the method further comprising: receiving a second working fluid, wherein the second working fluid including a plurality of different refrigerants with different boiling points; compressing the received second working fluid; releasing heat from the received second working fluid to generate a sixth cooled working fluid; releasing additional heat from the sixth cooled working fluid to a seventh cooled working fluid to generated an eighth cooled working fluid; constricting flow of the eighth cooled working fluid to generated a constricted eighth working fluid; and decreasing pressure of the constricted eight working fluid to generated a ninth cooled working fluid, wherein the first cooled working fluid is generated using the ninth cooled working fluid.
 20. The method of claim 15, wherein the working fluid is in a closed system.
 21. The method of claim 15, wherein the working fluid includes at least five different refrigerants with each have a different boiling point. 